www.ornitologiacolombiana.org/revista.htm Ornitología Colombiana Ornitología Colombiana Colombiana Ornitología si poder estoesdeterminar así númeronidos para examinar de especie undeberán mayor de la diaria actividad y parental veedoradealimento durante segundala mitad periododel de crianza fue prácticamentenulo. Futurosestudios del cuidado de pareja esta en neotropicales, no especies otras estas en ocurre que lo aembargo,neotropicales. noopuestoSintempladasáreas habitan queaves ymamíferosconsumidorasrapaces de aves resultadosEngeneral,viente. estudioloseste concuerdan de conlabores divisiónlaobservada deen hembras deymachos alimentaronpollono sobrevi-adultosedad yaal losde días los40 exclusiva hembra. actividadde casipartirA la fue de nes nomacho disminuyóelritmo de aporte de presas durantelosestadios finales deeste período. La alimentación de lospicho- El nido.el en crianza de período del 40 y 31días losentre ocasiones, dos en únicamente hembraaportópresas La 95.8%). ( macho del cargo a exclusivamentecasi estuvo presas de aporte el período,este En actividad. esta a tiempo su de crianzaenel nido hembrala dedicó de 62.2%períododesu tiempo el aatender Enelmismo mientras elque edad.machosolo consagró deun 10.9% días 56 los a nido elabandonó y sobrevivióhembra, una otro, el quemientras 12, y 8 días los entre murió unonacidos, pichones dos los De período. del tercio primer del luegoincubación la encargadade principal la Patagonia enla Sur,Argentina. ÁguilasMorasanidanteunapareja de actividad de diaria la cuidadoy elInvestigamosparental Resumen words:Key across completeits range should be investigated. length,thetime topography,parentalweather)(daycareand havein factors may adults,thatMoreover,size,availability,bioticfood(broodageofcompetition role pair. withthe otherpredators)abi and this uniqueto orspecies this in behaviorcommon a is this ifdetermine to nests number of larger examinea should studies significant a prey mammal largebird and other in observed sexes the between labor of division the with consistent are study this of results Overall, it. feedingstopped nearly parents the old, days >40 was nestling theAfter offspring. the of feeding the of most performed female The period.nestling the stagesof later during rateprovisioning hisreduce not did male The 40. and 31 days tween ( male theexclusively deliveredwasalmost by ing(s) thisDuringtimenestl-femaletheperiod,attendingtheforthepreyand10.9%male.forspentherof nest, female 62.2% vs. 8 days after survived female) (a which of one thewasfemalebut responsible alargerfor percentage stages middlelate theincubation.inandof Two chickshatched, only melanoleucus) We investigatedthe parentalcare andtime Abstract California,91767 USA 3 2 Argentina 1 R. Lucca De Eduardo urn Ades Clee f eeiay eiie Wsen nvriy f elh cecs 39 . eod t, Pomona, St., Second E. 309 Sciences, Health of University Western Medicine, Veterinary of College Address: Current Aires, Buenos (1646) Fernando San 1664, Febrero De 3 Argentina, de Predadores de Manejo y Estudios de Centro FacultaddeCiencias Veterinarias, Universidad deBuenos Aires,Buenos Aires, Argentina Black Cuidado parental y actividad diaria de unay Cuidado actividad pareja de anidanteparental diaria de Moras Águilas [email protected] Parentalcare timeand -

eating raptors from temperate regions outside of the Neotropics. However, in this pair the female did notbecome did female thepair this However, Neotropics.thein regionsoftemperateeating outsideraptorsfrom

Black - chested Buzzardchested in southern Patagonia, Argentina. Female and male shared daytime incubation (male 30.3%, female 69.7%),female 30.3%, (male incubation daytimeshared male and Female Argentina.Patagonia, southern in - - chestedBuzzard provider duringthe secondhalf theof nestling period;thewas male almost the onlyfood provider. Further

12: 12: 17 1

& Miguel D. Saggese MiguelD. &

- Laincubación estuvo acargo del macho (30.3%)hembray de la (69.7%),hembrapero la fue 24 southern Patagonia,southern Argentina melanoleucus) melanoleucus) -

Eagles , Geranoaetus melanoleucus, melanoleucus, Geranoaetus , - activity budgetof a breeding pair Blackof - - 12 of the nestling period and fledged at 56 days. In the nestling period, the period, nestling the In days. 56 at fledged and period nestling the of 12 eagles eagles - activitybudgetof a breeding pairof 2,3 n en la Patagoniala Argentina en Sur, =46, 95.8%). The female delivered prey to the nestling only twice,be- nestling theonly to femalepreyThedelivered 95.8%).=46,

17 (Geranoaetus melanoleucus) melanoleucus) (Geranoaetus

parentalcare, Patagonia,time G. melanoleucus G. - activitybudgetBlackof - chested

el papel de la hembra como pro- comohembra la de papel el

(Geranoaetus melanoleucus) melanoleucus) (Geranoaetus - activity budget - (Geranoaetus (Geranoaetus Eagles - chestedBuzzard (Geranoaetus (Geranoaetus

n n in in 2012 =46, oti

c - -

Artículo

De Lucca & Saggese común para la especie o un fenómeno exclusivo de esta pareja. Además, se deberá investigar el papel que factores bióticos (tamaño de la postura, edad de los adultos, disponibilidad de alimento, competencia con otros depredadores) y abióticos (extensión del período de horas luz, clima, topografía) pueden tener en determinar el cuidado parental y actividad diaria de G. melanoleucus en toda su distribución geográfica.

Palabras clave: Actividad diaria, Águila mora, Geranoaetus melanoleucus, cuidado parental, Patagonia

Introduction largest Buteonine raptors inhabiting open, tem- perate areas of South America (Jimenez & Jaksic Comparative studies of the breeding behavior of 1990). Reversed sexual dimorphism is marked in raptors indicate that feeding on insects, in- this species (Jimenez & Jaksic 1990). Its prey are vertebrates and reptiles have reduced sex-based small- and medium-sized mammals along most of division of labor during the breeding period com- its range (Jimenez & Jaksic 1990, Pavez et al. 1992, pared to species preying on mammals and , Trejo et al. 2006, but see also Zorzin et al. 2007 such as Buteonine , Accipiter hawks, larger and Salvador. et al. 2008 who described birds as falcons and eagles (Newton 1979, Olsen 1995, its main prey in Brazil). In Argentina, the Black- Gaibani & Csermely 2007). In species preying on chested Buzzard- is commonly found in mammals and birds, males and females have dif- Patagonian steppes, coastal areas, and savanna ferent roles during different stages of the nesting woodlands (Jimenez & Jaksic 1990). It is consid- season; males usually are the main food providers ered a common, non-threatened species through- during pre-incubation, incubation and early stages out its range, although local human persecutions, of chick development, whereas females are mainly collisions with power lines and poisonings have responsible for incubation of the eggs and brood- been reported (De Lucca & Saggese 1989, 1995, ing of the nestlings (the prey-partitioning hypoth- Bellati 2000, Alvarado & Roa 2010). Elements of esis; Newton 1979, Olsen 1995, Simmons 2000). In the behavioral ecology, agonistic behavior and later stages of the nestling period when food de- habitat selection of the species have been mands increase, females increase the time they reported (Jimenez & Jaksic 1989, Farquhar et al. spend hunting and providing food to nestlings 1994, Bustamante et al. 1997, Salvador et al. (Newton 1979, Olsen 1995, Simmons 2000, Gaiba- 2008). Its breeding ecology and nesting ecology ni & Csermely 2007). Most of the information on have been extensively studied along its distribution breeding behavior, parental care and time-activity in Argentina, Chile, Peru, Ecuador and Brazil budgets of large raptors that eat mammals and (Schoonmaker 1984, Sierra 1985, Jimenez & Jaksic, birds comes from studies conducted on Nearctic, 1990, Hiraldo et al. 1995, Travaini et al. 1994, De Palearctic, African and Australasian species (Brown Lucca & Saggese 1995, Donázar et al. 1996, 1977, Newton 1979, Cramp & Simmons 1980, Cardozo De Souza 1999, Pavez 2001, Saggese & Palmer 1988, Olsen 1995). The amount of behav- De Lucca 2001, 2004, Zorzin et al. 2007, Salvador ioral information available for Neotropical raptors et al. 2008). However, detailed observations of pa- is minimal (Bierregaard 1995, Trejo 2007). rental care and time-activity budgets have not been reported. In this study we examine the pa- The Black-chested Buzzard-eagle (Geranoaetus rental care and time-activity budget of a breeding melanoleucus) ranges from Venezuela and Co- pair of Black-chested Buzzard-Eagles in Santa lombia to Tierra del Fuego in southern Argentina Cruz province, a temperate area in southern Pata- and Chile (Jimenez & Jaksic 1990). It is one of the gonia, Argentina. www.ornitologiacolombiana.org/revista.htm 18 2012 | Número 12 Parental Care and Time-Activity Budget in Geranoaetus melanoleucus Methods Both members of the pair were in adult plumage and sexes were easily identified while flying, perch- The study was conducted from 20 Sep 1987 to 5 ing or incubating by unique plumage characteris- Jan 1988 (Patagonian spring and early summer) in tics (missing feathers), and size and color patterns Estancia El Cuadro, Department of Deseado, Santa of under-wing coverts, breast and abdominal Cruz Province, Argentina (47°30’S, 68°10’W), ap- feathers. Breeding periods were determined by di- proximately 150 km west of Puerto Deseado and rect observation of adult behaviors and by the 135 km from Jaramillo and Fitz Roy, the closest presence of eggs and chicks in the nest. Behaviors, towns by road. The study area is located in the time and activity budgets were recorded during Central Patagonia District within the Patagonian three different nesting periods of the nesting sea- Province phytogeographic region (Cabrera 1976). son defined as: (1) pre-incubation period (from 23 Topography is characterized by a succession of Sep to 7 Oct, total 2,276 min), (2) incubation peri- mesas, cliffs, valleys, and small canyons. Elevation od (from 8 Oct to 12 Nov, total 8,781 min [further ranges from 150 to 290 m. The vegetation is typi- divided into early, mid-, and late incubation stages cal of the Central Patagonia District, dominated by of 3,960, 2,550 and 2,271 min, each 12 days long]) tussock grasses (Stipa spp., Poa spp.) and small and (3) nestling period (from 13 Nov to 2 Jan, total shrubs such as Algarrobo Patagónico (Prosopis 11,400 min). This last period was separated into denudans), Molle (Schinus sp.), Quilembay two early nestling stages of 10 days each (days 1 (Chuquiraga avellanedae), and Calafate (Berberis to 10, 2,390 min and days 11 to 20, 2,839 min) cuneata) (Cabrera 1976). Wet meadows (locally and two later nestling stages of 10 days each (days called mallines) and small ponds formed by rainfall 31 to 40, 4,226 min and days 41 to 50, 1,945 min). and natural springs are found scattered in the val- No observations were conducted between days 21 leys. During 1987-1988 sheep ranching was the and 30. main human activity in the study area; the vegeta- tion showed severe signs of overgrazing. Several Nesting material delivery and prey provisioning aspects of the breeding ecology of Black-chested rates were defined as the number of events per Buzzard-Eagles and additional characteristics of hour of observation. Additional details of behavior the study area have been described elsewhere (De were recorded and categorized for adults and the Lucca & Saggese 1995, Saggese & De Lucca 1995, single nestling. Activity is expressed here as per- 2001, 2004). centage and/or as a rate of events (e.g. feeding or mating events) per hr of the total observation time We monitored one pair of eagles from a blind lo- for the whole study or for each period/stage as cated 70 m from the nest and used 7 X and 10 X defined above. For each member of the pair, 50 binoculars for detailed observations and quan- events included: time spent away from the nesting tification of the parental care and time-activity cliff (out of sight, e.g., hunting) perching on the budget. Observations covered a total of 374 h 17 nesting cliff (rocks and trees), incubating, providing min (22,457 min) of direct monitoring using an an- nest material, brooding, standing on the nest, imal and nest focal technique (Lehner 1979). Ob- feeding (itself, nestling or mate). servations were conducted at randomly selected periods and times of day, from sunrise to sunset. Results In spring observations started at 07:00 h and end- ed by 19:00 h; near the summer solstice we con- Pre-incubation period. By the time our observa- ducted observations from 06:00 to 21:30 h. tions began at the initiation of this study, the pair www.ornitologiacolombiana.org/revista.htm 19 2012 | Número 12 De Lucca & Saggese spent most of their day time flying and performing 80 courtship and territorial displays (66.5% and 81.8% 70 of the daily time for the female and male, respec- 60 tively). The female spent more time at the nest 50 40 (11.8%) and perching at the nesting cliff (21.6%) Male

Percentage 30 Female than the male (1.1% and 17.1%, respectively). Both 20 members of the pair were seen together at the 10 nest during 0.6% of this period. The nest was left 0 unattended 87.7% of this time. Yellow tussock early middle late grasses were delivered to the nest by both mem- Incubation period bers on 12 occasions (0.32 deliveries per h); the Figure 1. Percentage of daytime spent incubating by sex in a male made 5 (41.6%) and the female 7 (58.3%) of pair of Geranoaetus melanoleucus during three stages of the them. Copulation was observed on five occasions incubation period. in this period at a rate of 0.13 mating events per 14 hour (Saggese & De Lucca 2001). 12

10 Incubation period. We first observed incubation 8 and confirmed a clutch of two eggs on 8 October. 6 The female spent 65.0% of the time at the nest, Male Percentage Female 88.1% of this time incubating and overall being re- 4 sponsible for 69.7% of the time eggs were incu- 2 bated. She spent the remaining time out of the 0 early middle late nest feeding and gathering nesting material Incubation period (31.0%) or perched on the nest cliff (3.9%). The male spent 35.4% of this period at the nest, 85.6% of this time incubating and overall being responsi- Figure 2. Percentage of daytime spent perching on the nest- ing cliff by members of a pair of Geranoaetus melanoleucus ble for 30.3% of the time eggs were incubated. He during three stages of the incubation period. spent the remaining time perching at the nest

(5.1%), perching on the nesting cliff (10.7%) and 80 flying or out of sight (53.9%). The nest was unat- 70 tended only 1.3% of this period (Fig. 2). 60

50

During the early incubation stage the male partici- 40 pated more in incubation than in later stages (Figs. Male 30

1 and 2). In contrast, the percent of time the fe- Percentage Female 20 male spent incubating increased from the first to 10 the second stage and then decreased at the end 0 (third stage) of this period, when temperatures early middle late were extremely high and sun rays pointed directly Incubation period on the nesting cliff (Fig 1.). The male spent sub- stantial time away from the nesting cliff and this Figure 3. Percentage of daytime spent away from the nesting absence steadily increased during the incubation cliff by members of a pair of Geranoaetus melanoleucus period (Fig. 3). As incubation progressed, the fe- during three stages of the incubation period. www.ornitologiacolombiana.org/revista.htm 20 2012 | Número 12 Parental Care and Time-Activity Budget in Geranoaetus melanoleucus male spent less time away from the nest cliff and parents almost ceased feeding it (Table 1). At this less time perched on the cliff, spending most of age, the chick fed itself 4 times (2.3% of the time her time incubating (Figs. 1-3). During the incuba- activity budget of this chick during this stage) at a tion period the parents delivered yellow, dry, tus- rate of 0.12 feeding events per hour. Duration of sock grass to the nest on 20 occasions, at a rate of these events averaged 12 min (range 1-25 min). 0.136 deliveries per hour. The female contributed materials on 15 (75%) occasions and the male five Discussion (25%) times. For most of the behaviors studied here, the male Nestling period. Two chicks hatched at this nest; and female Black-chested Buzzard-Eagles had one of them disappeared between 8 and 12 days clearly distinct roles during the different stages of of age, and the other fledged at 56 days. The sin- the breeding cycle. This is consistent with the role gle offspring that fledged was a female, as deter- of males and females in well-studied non- mined morphometrically (Saggese & De Lucca Neotropical Buteonine hawks and eagles from 2001) at the end of the study. During the nestling temperate areas that also feed on mammals and period the adult female spent most of her time at birds (Brown 1977, Newton 1979, Cramp & Sim- the nest (62.2%). The remaining time was spent mons 1980, Olsen 1995). One important differ- perching on the nesting cliff (14.1%) or either fly- ence relative to other similar large-bodied raptor ing near the nesting site and flying or performing species observed in this study was the limited par- other activities out of sight (23.7%). In contrast, the ticipation of the female in providing food to the male spent only 10.9% of his time at the nest; the nestling late in the nestling period; the male was remainder of his time was spent either perching the main and almost exclusive food provider dur- on the nesting cliff (15.6%) or flying near the cliff ing the whole nestling period. These findings do and out of sight (73.9%). The male and female not fully support the prey-partitioning hypothesis, were together on the nest only 3.1% of the time. at least with regard to an increased involvement of Overall, the nest was unattended 30% of the nestl- the female in providing prey during the second ing period. half of the nestling period. Whether this represents a distinctive characteristic of this species or a trait The parents delivered yellow tussock grasses to of this particular pair is not known. the nest 20 times; the female brought most of the material (n = 19; 95%) at a rate of 0.11 deliveries Pavez (2001) and Salvador et al. (2008) also ob- per h. In contrast, prey was almost exclusively served limited involvement of female Black- provided by the male (n = 46; 95.8%) at a provi- chested Buzzard-Eagles in providing prey to the sioning rate of 0.25 prey deliveries per h. The fe- nestlings, but the provisioning rate and the exact male provided prey on only two occasions (4.2% stage of the nestling period when female provi- of the total prey provided to the nest). Both events sioning happened was not reported in those stud- occurred when the nestling was 31-40 days old. ies. However, the results of those studies and ours may support the hypothesis that female Black- The nestling was fed almost exclusively by the fe- chested Buzzard-Eagles have limited involvement male; the duration of feeding events ranged from in providing prey to the nestlings. Alternative ex- 1 to 37 min (Table 1, mean = 12.1 min). Feeding planations may be related to the number of nest- involved only 5.3% of the time-activity budget in lings in broods (in this study only one for most of this period. After the nestling was >40 days old, the time, thus reducing the demands), potential www.ornitologiacolombiana.org/revista.htm 21 2012 | Número 12 De Lucca & Saggese Table 1. Time-activity budget of male and female Geranoaetus melanoleucus during the nestling period.

Activity Days in nestling period Days 1-10 Days 11-20 Days 31-40 Days 41-50 Observation time (min/h) 2,390/39.83 2,839/47.31 4,226/70.43 1,945/32.41 Feeding (events and rate) 2 1 Male 0 0 (0.028/h) (0.030/h) 16 14 14 Female 0 (0.401/h) (0.295/h) (0.199/h) 16 14 16 1 Total (0.401/h) (0.295/h) (0.227/h) (0.030/h) Duration (mean and range) 9.5 15.63 11.69 NA (3-25) (6-26) (1-37) Nest material provisioning (events and rate) 1 Male 0 0 0 (0.014/h) 2 3 9 5 Female (0.050/h) (0.063/h) (0.127/h) (0.154/h) 2 3 10 5 Total (0.05/hr) (0.063/hr) (0.141/hr) (0.154/hr) Food provisioning (events and rate)

7 11 20 8 Male (0.175/h) (0.232/h) (0.283/h) (0.246/h) 2 Female 0 0 0 (0.028/h) 7 11 22 8 Total (0.175/h) (0.232/h) (0.312/h) (0.246/h) Male attending nest (%) Brooding 0.014 0 0 0 Feeding nestling 0 0 0.23 0.15 Total 12.55 9.58 12.49 7.66 Female attending the nest (%) Brooding 53.76 3.56 0 0 Feeding nestling 6.34 7.71 4.42 0 Total 86.23 79.40 49.26 34.09 Nestlings unattended (%) 4.44 14.97 40.87 59.69 Perching at nesting site (cliff, trees) (%) Male 11.38 11.73 17.96 18.20 Female 2.80 3.73 20.16 30.13 Out of sight (flying, displaying, hunting) (%) Male 76.06 78.69 69.55 74.14 Female 10.96 16.87 29.98 35.78 www.ornitologiacolombiana.org/revista.htm 22 2012 | Número 12 Parental Care and Time-Activity Budget in Geranoaetus melanoleucus nest predators in the vicinity, or intra-pair varia- lines in Calera de Tango, Chile. Spizaetus 9:11-14. tions in provisioning their nestlings, as individual BELLATI, J. 2000. Behavior and relative abundance of the rap- tors of the Andean foothills of Argentina. Ornitología Ne- differences in the division of labor between the otropical 11:207-222. sexes are known to occur among birds of prey BIERREGAARD, R. O. JR. 1995. The biology and conservation (Newton 1979). In some species of raptors the fe- status of Central and South American Falconiformes: a male does not do any appreciable hunting until survey of current knowledge. Conservation Interna- the young fledge; female participation seems to tional 5:325-340. BOULET, M., P. OLSEN, A. COCKBURN, & K. NEWGRAIN. 2001. Pa- be dependent on the male’s ability to provide rental investment in male and female offspring by the food during this period, and, when food is abun- peregrine falcon, Falco peregrinus. The Emu 101:95-103. dantly provided by the male, the female is less ob- BROWN, L. 1977. Eagles of the world. Universe books, New ligated to leave the nest and hunt to provide food York, New York, USA. to the nestlings (Newton 1979). Both parental care BUSTAMANTE, J., A. DONÁZAR, F. HIRALDO, O CEBALLOS, & A. TRAVAINI. 1997. Differential habitat selection by immature and time-activity budgets of male and female rap- and adult grey eagle-, Geranoaetus melanoleu- tors may vary as result of several biotic (e.g., cus. The Ibis 139:322-330. brood size, age of adults, food availability, compe- CABRERA, A. L. 1976. Regiones fitogeográficas argentinas. En- tition with other predators) and abiotic (e.g., day ciclopedia argentina de agricultura y jardinería. Tomo II, length, topography, weather) factors (Boulet et al. ACME, Buenos Aires, Argentina. CARDOZO DE SOUZA, M. 1999. Reproduçao e hábitos alimen- 2001, Palmer et al. 2001). Further studies examin- tares de Geranoaetus melanoleucus (Falconiformes: Ac- ing a larger number of nests and investigating the- cipitridae) nos Estados de Sergipe e Alagoas, Brasil. Ara- se factors are necessary to better understand pa- jajuba 7:135-137. rental care and time-activity budgets of Black- CRAMP, S, & K. E. L SIMMONS. 1980. Handbook of the birds of chested Buzzard-Eagles over its extensive distribu- Europe, the Middle East and North Africa vol 2. Hawks to bustards. Oxford University press, Oxford, Oxfordshire, tional range. UK. DE LUCCA, E. R., & M. D. SAGGESE. 1989. Rapaces de la Pata- Acknowledgements gonia: factores que las afectan. Nuestras Aves 17:33. DE LUCCA, E. R. & M. D. SAGGESE. 1995. Fratricidio en el Aguila This research was possible thanks to the economic Mora Geranoaetus melanoleucus. El Hornero 14:38-39. DONÁZAR, J. A., A. TRAVAINI, & F. HIRALDO. 1996. Nesting asso- and logistic support provided by Fundación Vida ciation of raptors and buff-necked ibis in the Argentinean Silvestre Argentina, Fuerza Aérea Argentina, Ad- Patagonia. Colonial Waterbird 19:111-115. ministración de Parques Nacionales, Aves Argenti- FARQUHAR, C. C., W. S. CLARK, R. G. WRIGHT, & M. COELLO. nas, Gobierno de la Provincia de Santa Cruz, In- 1994. First record of interspecific cartwheeling between tendencia, Casa de Cultura y Museo del Hombre large raptors: poecilochrous and Geranoaetus melanoleucus. Journal of Raptor Research 28: 274-275. de Caleta Olivia and Museo de Ciencias Naturales GAIBANI, G., & D. CSERMELY. 2007. Behavioral studies. pp. 117- Bernardino Rivadavia. We are also very grateful to 128. in: D. M. Bird, and K.L. Bildstein (eds.) Raptor re- A. Trejo, S. Seipke, D. Ellis, W. Nelson, R. search and management techniques. Hancock House, Bierregaard, C. Farquhar and L. Depette for their Surrey, British Columbia, Canadá. helpful comments on this manuscript. We dedicate HIRALDO, F., J. A. DONAZAR, O. CEBALLOS, A. TRAVAINI, J. BUSTA- MANTE, & M. FUNES. 1995. Breeding biology of a grey this communication to the memory of Dr. J. R. Na- Buzzard-eagle population in Patagonia. Wilson Bulletin vas and J. C. Chebez. 107:675-685. JIMENEZ, J. E., & F. M. JAKSIC. 1989. Behavioral ecology of grey Literature cited eagle-buzzards, Geranoaetus melanoleucus, in central Chile. The Condor 91:913-921. JIMENEZ, J. E., & F. M. JAKSIC. 1990. Historia natural del águila ALVARADO, S., & M. ROA. 2010. Electrocution of black-chested Geranoaetus melanoleucus: una revisión. El Hornero buzzard-eagles (Geranoaetus melanoleucus) on power 13:97-110. www.ornitologiacolombiana.org/revista.htm 23 2012 | Número 12 De Lucca & Saggese

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Recibido: 29 de septiembre de 2011. Aceptado: 16 de octubre de 2012.

www.ornitologiacolombiana.org/revista.htm 24 2012 | Número 12